Extension and locking assembly for dripless element, and container therefore

ABSTRACT

A filter assembly includes housing enclosing a replaceable filter element. A support core is provided in the housing, and includes an extension and locking assembly. The element includes a ring of filtration media with a pair of end caps. The first end cap includes a central opening to receive the support core. The extension and locking assembly prevents the cover of the housing from being attached to the housing body without a proper filter element installed. The extension and locking assembly includes a bypass member and a locking member, which are in locking engagement when an element is absent in the housing. The second end cap includes internal protrusions which engage the locking member when the filter element is installed to disengage the bypass member from the support core, and allow the element to be inserted and the cover to be installed.

RELATED CASES

This application is a continuation of U.S. patent application Ser. No.10/989,776, filed Nov. 16, 2004; which is a continuation of U.S. patentapplication Ser. No. 10/371,751, filed Feb. 21, 2003, now U.S. Pat. No.6,837,993; which is a divisional of U.S. patent application Ser. No.09/584,972, filed Jun. 1, 2000, now U.S. Pat. No. 6,554,139, thedisclosures of which are incorporated herein by reference.

FIELD OF THE INVENTION

This invention relates to fluid filters, and more particularly to fuelfilters for vehicles.

BACKGROUND OF THE INVENTION

Many types of filters (also referred to as “separators”) are known inthe prior art. Filters are widely known for removing contaminants andother impurities from fluids such as fuel and oil. A popular type offilter has a housing that encloses a replaceable ring-shaped filterelement. The filter element ensures that impurities are removed fromfuel or oil before it is delivered to system components such as fuelinjection pumps and fuel injectors. Mating portions of the housing forman interior enclosure for the element, and the housing portions may beseparated for replacement of a spent filter element. Periodicreplacement of the filter element is required so that the filter elementwill not become so loaded with impurities that flow is restricted. It isknown that problems may arise when such filter elements are replaced.

One problem is that filter elements with different sizes and/orfiltration capabilities often have identical mounting configurations andcan fit on the same filter head. However, use of the wrong filterelement can cause poor engine performance and allow undesirable amountsof contaminants to pass through the system.

Another problem is that individuals may remove a spent filter elementand simply re-attach the housing portions without a fresh element. If anautomatic drain valve is used in the filter (see, e.g., U.S. Pat. No.5,468,386), fuel or oil can be dumped to drain when an element is notinstalled in the housing. While the engine may operate (at least for ashort period of time), this can be detrimental to the engine,particularly if the operation of the engine depends on the continuedsupply of oil or fuel from the filter.

A still further problem is that upon removing the element, an individualmay come into contact with the fuel/oil and any impurities on theelement, and get dirty hands. The user typically has to reach down intothe housing to grasp the element, and may come into contact withresidual fuel or oil in the housing and on the element. In addition, anyfuel or oil remaining on the element may drip off on the surroundingengine components when the element is removed, thereby fouling theengine; or worse yet, drip off onto the ground and create environmentalissues.

To reduce and at least partially eliminate some of these problems, thefilter assembly shown in U.S. Pat. No. 4,836,923, owned by the Assigneeof the present application, was developed. This filter assembly includesa unique replaceable filter element that is attached to a removablecover. The filter element includes an opening in one end cap oppositefrom the cover, which allows the filter element to be removeably locatedover an elongated standpipe in the housing. The element is removed whenthe cover is removed (screwed off) from the housing. While this reducesskin contact with the element and thereby reduces the mess associatedwith an element change, this does not fully address the problem withfuel, oil and impurities draining off the element as it is removed fromthe housing and carried across the engine.

In addition, the cover of the housing in the '923 patent is typicallydiscarded with each spent element. This is undesirable from aconservation and solid waste standpoint, as the cover is usually a heavyplastic or metal component. It is generally desirable to minimize theamount of material discarded, particularly if a discarded element mustbe treated as hazardous waste and/or cannot be easily incinerated. Thecover also represents a portion of the cost of the replacement element.As a result, this design adds cost to the replacement element.

The element in the '923 patent may also be separated from the cover, andthe cover re-attached to the housing without a fresh element also beinginstalled. As such, this design does not fully address the problemsassociated with operating an engine without a filter element installed.

An improved filter assembly is shown in U.S. Pat. No. 5,770,065, alsoowned by the assignee of the present application. In this patent, astandpipe is similarly provided internally to the housing, and aspring-biased valve element is provided internal to the standpipe. Thevalve element is normally closed, and can be engaged and moved to anopen position by a projection on an end cap of the element when theelement is properly installed in the housing. The valve (and hence thefilter assembly) generally cannot be operated without a proper filterelement installed. The filter shown in the '065 patent overcomes some ofthe problems associated with the earlier '923 patent, however, the coveris attached to the element in the same manner as in the '923 patent, andfuel and oil can still drip onto the engine and the surrounding areawhen the filter element is replaced. Also, as in the '923 patent, thecover may be detached from the element and screwed back onto the housingwith out a fresh element being installed. In some high-pressure fuelsystems, the valve element may actually be forced open, and unfilteredfuel can be allowed to pass to the downstream components. This can alsobe detrimental to the engine.

It is therefor believed there exists a need for a still further filterthat reduces if not eliminates, the mess and environmental issuesassociated with changing an element; and prevents the operation of thefilter without a proper filter element.

SUMMARY OF THE PRESENT INVENTION

A new and unique filter assembly is provided that prevents an improperfilter element from being used in the filter and prevents operation ofthe filter without a filter element in place. Mess and environmentalissues are substantially reduced, if not eliminated, during an elementchange. The filter element is also simple and low-cost to manufacture.

According to the present invention, the filter assembly includes areplaceable element with a ring of filtration media, and an end capsealingly bonded to either end of the filtration media. An internalsupport core is fixed to an end wall of the filter housing, and one ofthe end caps of the filter element include a central opening, such thatthe filter element can be removably received over the support core. Thesupport core provides internal support for the filter element, so thatthe filter element can be composed of only material which is easilyincinerated.

An extension and locking assembly is provided with the support core. Theextension and locking assembly operates to prevent the cover of thehousing from being attached to the housing body without a proper filterelement installed in the housing, or without a filter element in thehousing. The extension and locking assembly includes a bypass member anda locking member. The bypass member is closely and slideably received inthe locking member, while the locking member is closely and slideablyreceived in the support core. In one embodiment, both the locking memberand the bypass member have enlarged heads, with the enlarged head of thebypass member overlying the enlarged head of the locking member. A mainspring extends between a shoulder on the support core and the enlargedhead of the locking member to bias the locking member and bypass memberoutwardly from the support core.

When the locking member and bypass member are in their outer position,the distal inner end of the locking member urges the distal inner end ofthe bypass member radially outward against the inner surface of thesupport core. The support core includes an annular step or shoulderalong its inner surface, and the distal inner end of the bypass memberengages the step to prevent the extension and locking assembly frombeing pushed inwardly into the support core. The extension and lockingassembly is long enough such that the cover of the housing cannot beattached to the housing body when the extension and locking assembly isin its outer position.

The enlarged head of the bypass member includes a series of openingswhich allow access to the enlarged head of the locking member. Theopenings are strategically placed, and the other end cap (opposite fromthe end cap of the filter element with the central opening) has a seriesof protrusions that extend axially inward from the end cap, inorientation with the openings. When the element is installed over thesupport core, the protrusions extend through the openings in the head ofthe bypass member and engage the head of the locking member. Theprotrusions force the locking member axially inward, and in so doing,move the distal inner end of the locking member away from the distalinner end of the bypass member. This allows the distal inner end of thebypass member to disengage from the step in the support core, and thelocking member and bypass member to slide inwardly (retract) into thesupport core. In its inner position, the extension and locking assemblyallows the filter element to be properly located in the filter housing,and the cover to be attached to the housing body.

As should be appreciated, a filter element without a correct arrangementof protrusions on its end cap will not engage the head of the lockingmember, and the extension and locking assembly will remain locking inits outer position, thereby preventing the filter element from beingproperly assembled in the filter housing.

Another feature of the filter assembly is that during an element change,when the cover is removed, the extension and locking assembly will urgethe spent element slightly outwardly from the housing, as the extensionand locking assembly moves to its outer position. This facilitatesremoving the spent filter element from the housing, and reduces contactwith any fuel or oil remaining in the housing.

A bypass valve can be provided in the bypass member to allow fluid tobypass the filter element when the filter element becomes clogged withimpurities. The bypass valve can be provided as a unitary piece with thebypass member, or as a separate piece supported by the bypass member. Abypass spring biases the head of the bypass valve against a centralopening in the adjacent end cap to normally prevent fluid bypassing theelement, but to allow fluid bypass when the pressure in the housingincreases above a predetermined amount.

As discussed above, the filter element includes a pair of end caps, witha first of the end caps including a central opening to receive thecentral support core. The second end cap includes the protrusions foroperating the extension and locking assembly, and can include a centralopening if the bypass valve is used. The central opening in the secondend cap is preferably bounded by a short annular flange, which extendsinwardly into the filter element, and seals against the bypass valvewhen the element is located in the housing. The flange and protrusionscan be easily formed with the end cap such as by molding the end cap asa unitary component, and the filter element is otherwise a simple andinexpensive component to manufacture. While not as preferred, theprotrusions could also be formed on a separate piece and held againstthe inside surface of the second end cap.

Another feature of the present invention is that the filter element ispreferably stored for shipment in a fluid-tight container. The containerincludes a cup-shaped body and a lid, with the lid being easilyattachable to the body to allow easy access to the filter element. Thebody and lid are preferably formed from inexpensive, lightweight,incineratable material, for example, a plastic. The container bodyincludes a retaining device, such as a ridge or bead, integral witheither the sidewall and/or end wall of the body, which is designed toengage an appropriate part of the element and retain the element in thebody. The retaining device can have a number of different forms, and canbe configured to engage different locations on the filter element toretain the element within the container body. It is preferred that theretaining device be resilient, and resiliently deflect to engage aportion of the end cap, such as the outer periphery of one of the endcaps.

During an element change, a fresh element can be removed from thecontainer and set aside. The empty body of the container is theninverted, and inserted open-end first into the open end of the filterhousing, in surrounding relation to the spent element. This isfacilitated by the element sitting slightly outwardly from the housingas discussed above. The resilient retaining device engages the element,and cooperates with the element to retain the element to the body. Thecontainer body is then removed from the housing, with the elementattached thereto. Upon removing the body from the housing, the body isimmediately turned upright, thereby preventing any fuel or oil fromdripping off the element and contaminating the surrounding area. The lidis then attached to the body, and the entire assembly, with the spentelement, can then be disposed of such as by incineration.

Thus, as described above, the filter of the present invention preventsan improper filter element from being used in the filter, and preventsoperation of the filter without a filter element in place. Mess andenvironmental issues are substantially reduced, if not eliminated,during an element change. The filter element is also simple and low-costto manufacture.

Further features and advantages will be apparent upon reviewing thefollowing Detailed Description of the Preferred Embodiment and theaccompanying Drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevated perspective view in partial cross section of afirst embodiment of the filter constructed according to the principlesof the present invention;

FIG. 2 is a cross-sectional side view of a portion of the filter shownin FIG. 1;

FIG. 3 is an exploded view of certain components of the filter of FIG.1;

FIG. 4 is a cross-sectional side view of a portion of the filter of FIG.1, illustrating the outer position of the extension and lockingassembly;

FIG. 5 is an enlarged view of a portion of the filter of FIG. 4;

FIG. 6 is an elevated perspective view of the extension and lockingassembly for the filter of FIG. 1;

FIG. 7 is an inside view of the upper end cap for the filter element;

FIG. 8 is a cross-sectional side view of the extension and lockingassembly, illustrating the end cap of the filter element engaging thelocking member;

FIG. 9 is cross-sectional side view of the filter, illustrating theextension and locking assembly in an outer position;

FIG. 10 is a cross-sectional side view of the extension and lockingassembly shown constructed according to a further embodiment of thepresent invention;

FIG. 11 is an exploded view of the extension and locking assembly ofFIG. 10;

FIG. 12 is an elevated perspective view of a separate end piece withprotrusions for the filter of FIG. 1;

FIG. 13 is an exploded view of the container and a fresh element for thefuel filter of FIG. 1;

FIG. 14 is a cross-sectional side view of a first embodiment of thecontainer for the filter element;

FIG. 15 is an enlarged view of a portion of the container of FIG. 14;

FIG. 16 is a cross-sectional enlarged view of another portion of thecontainer of FIG. 14;

FIG. 17 is a cross-sectional enlarged side view of a portion of thecontainer, illustrating a second embodiment of the container;

FIG. 18 is a cross-sectional side view of a third embodiment of thecontainer;

FIG. 19 is an elevated perspective view of a fourth embodiment of thecontainer;

FIG. 20 is a cross-sectional side view of the container, illustrating afifth embodiment of the container;

FIG. 21 is an enlarged view of a portion of the container of FIG. 20;and

FIG. 22 is a cross-sectional side view of a sixth embodiment of thecontainer.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings, and initially to FIG. 1, a firstembodiment of a filter constructed according to the principles of thepresent invention, is indicated generally at 30. The filter 30 isparticularly suited for filtering water and other particulate andcontaminants from fuel (e.g., diesel fuel), but is generally appropriatefor separating any low density fluid (e.g., water) from a higher densityfluid (e.g., oil). The filter 30 of the first embodiment includes anannular housing body 32 with a cup-shaped cover 34 removeably attachedto an open end of the housing body. The housing body 32 and cover 34define an interior cavity 35 for a removable filter element 36. Housing32 and cover 34 are formed from materials appropriate for the particularapplication, for example hard plastic, and the housing 32 is fixed to anappropriate location on the engine.

Annular housing body 32 includes a disk-shaped end wall 37, an inletport 38 and an outlet port 39 which direct fuel into and out of thefilter. The inlet and outlet ports are illustrated as being formed inthe end wall 37, however one or both could also be formed in housingbody 32, or even in cover 34. In any case, fuel (or oil) to be filteredis directed through inlet port 38 and into a peripheral region 40 of thefilter, between housing body 32 and filter element 36. The fuel thenpasses radially inward through element 36, wherecontaminants/particulate in the fuel are removed, and the filtered fuelthen passes through port 39 to the downstream components of the fuelsystem.

The housing body 32 includes an open end 42, and a series of internalthreads 44 are provided near the open end. The cover 34 also includes anopen end 46, with a series of external threads 48 provided near the openend. Threads 44 of housing cooperate with threads 48 of cover 34 toenable the cover to be easily screwed onto and off of the housing. AnO-ring seal or gasket 50 is provided between the housing components toprovide a fluid-tight seal. The above is only one technique forattaching the cover to the housing, and other techniques are possible asshould be known to those skilled in the art.

A threaded spud or collar 54 is provided centrally in the end wall 37 ofthe housing, and bounds outlet port 39. Spud 54 projects axially upwarda short distance from the end wall 37 toward the open end 42 of thehousing body.

If necessary or desirable, an automatic drain valve (not shown) can beinstalled in the end wall 37 of the housing, such as described in U.S.Pat. No. 5,468,386. This patent is incorporated herein by reference.

Referring now to FIGS. 2–5, a support core or tube 56 extends along theaxial center line of the housing, and includes a threaded inner end 57which is screwed into and sealingly received in spud 54. The inner endof the support core includes a short annular skirt 58 (see also FIG. 8)which is radially outwardly spaced from the core, and is closelyoutwardly received around spud 54. The support core 56 includes a seriesof ribs or flights as at 60 along its length. Flights 60 preferablyextend in a continuous helix, and facilitate the movement of fuel alongthe length of the support core, as well as provide uniform support alongthe inside surface of the filter element 36. The support core 56preferably has one or more openings 62 (FIG. 3) toward its outer (upper)end 64 to allow fuel to pass inward into the support core. The remainderof the length of the support core can be imperforate, or may also haveappropriate openings, depending upon the desired level of fuel to bemaintained in the support core. In certain situations, it is desired tomaintain a certain level of fuel in the support core for the smoothoperation of the filter during start-up. Finally, the support coreincludes an outer annular shoulder 66 and an inner annular step 68 (FIG.5), both at appropriate locations along the length of the core, and thereasons for which will be described below. Support core 56 is formed ofmaterial, e.g., hard plastic, appropriate for the particularapplication.

An extension and locking assembly, indicated generally at 70 in FIG. 4,is received in support core 56. Extension and locking assembly 70prevents the cover 34 from being attached to housing body 32 unless aproper filter element is installed in the housing. To this end, theextension and locking assembly 70 include a locking member 74 and abypass member 76; with locking member 74 being closely and slidinglyreceived in bypass member 76, and bypass member 76 being closely andslidingly received in support core 56. As shown in FIG. 3, lockingmember 74 includes a body 78 with a series of lower openings 79 forfluid flow, a series of upper openings 80, an annular base 82, and anenlarged annular head 84. The base 82 of the locking member includes aradially-outward projecting annular flange 86 (see FIG. 5). Body 78includes a series of inner axial channels or slots 90, which arepositioned to slidingly receive fingers 92 of bypass member 76. Lockingmember 74 is preferably formed unitarily (in one piece) from appropriatematerial, such as hard plastic.

Bypass member 76 includes fingers 92 and an enlarged annular head 94which overlays the enlarged annular head 84 of locking member 74 whenfingers 92 are received in channels 90. Fingers 92 extend along slots 90in locking member 74, and project outwardly (downwardly in the Figures)through upper openings 80. An imperforate dome-shaped end wall 96 isprovided radially inwardly of head 94, as shown in FIG. 4. Bypass member76 is also preferably formed unitarily (in one piece) from appropriatematerial, such as hard plastic.

A main spring 100 is provided in surrounding relation to the outer(upper) end of support core 56 and the locking member 74 and bypassmember 76. Spring 100 extends between annular shoulder 66 on supportcore 56 and the enlarged head 84 of locking member 74. Spring 100 urgesthe head of locking member 74 against the head of bypass member 76, andhence urges these components axially outward from support core 56. Whenthe bypass member 76 is received in locking member 74, fingers 92 ofbypass member 76 project axially through openings 80 in locking member74 and are received between the annular base 82 of the locking memberand the inside surface of the support core, as best seen in FIG. 5. Theannular flange 86 of the base 82 urges the fingers 92 radially outwardagainst the inner surface of the support core, and creates aninterference fit to retain the locking member and bypass member in thesupport core, that is, to prevent the main spring 100 from pushing thesecomponents entirely outwardly from the support core. A bypass spring 102is provided internally of the dome-shaped end wall 96 (as seen in FIG.4), and biases bypass member 76 outwardly away from locking member 74.Bypass spring 102 extends between the dome-shaped end wall 96 and aradially inward directed annular spring stop 106 (FIG. 2) on lockingmember 74.

As indicated above, the extension and locking assembly preventsattachment of the cover 34 to the housing body 32 without a properfilter element installed in the housing. As illustrated in FIG. 4, themain spring 100 normally urges the locking member and bypass memberoutwardly such that the distal inner ends of the fingers 92 of thebypass member 76 are axially outward of the annular step 68 (FIG. 5) inthe support core. The annular base 82 of the locking member 74 urges thefingers 92 radially outward against the support core, such that thefingers engage the step and prevent the extension and locking assemblyfrom being pushed inwardly into the support core. As illustrated in FIG.9, the extension and locking assembly 70 has an axial length sufficientthat the cover 34 cannot be fully screwed onto the housing body 32 whenthe extension and locking assembly is in its outer position.

To disengage the bypass member from the step in the support core, thebase 82 of the locking member is moved axially away (inwardly) from thedistal ends of the fingers 92 of the bypass member. As shown in FIG. 6,the head 94 of the bypass member has a series of openings 110 that allowaccess to the underlying head 84 of the locking member. The filterelement has an end cap 114, which as shown in FIG. 7, has a series ofdistinct, axially-extending protrusions 116 corresponding to thelocation of the openings 110 in the bypass valve head 94. Asillustrated, four such protrusions 116 are shown in a generallyevenly-spaced annular arrangement extending outwardly, away from the endcap 114, however the number and spacing of the protrusions can varydepending upon the number and location of openings 110, and it is notedthat only a single protrusion may be necessary in some applications. Thedistal ends of the protrusions 116, and/or the lands 118 between theopenings 110, can have angled or helical ramped surfaces, to facilitatethe orientation of the protrusions with the openings 110. The angled orhelical surfaces force or urge the filter element to rotate when theelement is installed in the housing such that the protrusions 116automatically become aligned with the openings 110.

When the filter element is installed in the housing, the protrusions 116on the end cap 114 project through openings 110, and engage the head 84of the locking member 74. The protrusions 116 force the locking memberaxially inward into the support core, as shown in FIGS. 2 and 8. Thebase 82 of the locking member moves axially away from the inner ends offingers 92 of bypass member 76, thereby allowing the fingers todisengage from step 68 and the bypass member to slide inwardly into thesupport core. This allows the extension and locking assembly to retractinto the support core, compressing main spring 100, and allows the cover34 to be attached to the housing body 32. The length of the protrusionsnecessary to move the locking member an appropriate axial distance canbe easily determined.

It should be appreciated that an element without a proper arrangement ofprotrusion(s) will not engage the head of the locking member, and theextension and locking assembly will remain locked in its outer position.It will not be possible to attach the cover 34 to the housing body 32.Thus, the invention not only prevents the operation of the filterwithout a filter element installed, but also prevents the operation ofthe filter even if an element is installed, but where the element failsto have a proper arrangement of protrusion(s).

Referring again to FIGS. 2 and 3, the filter element 36 includes a ringof filtration media 120 formed of an appropriate material in anappropriate manner. The element also includes a disk-shaped end cap 114sealingly bonded (such as with adhesive) to the outer (upper) end of themedia ring; and an opposite disk-shaped end cap 122 sealingly bonded(such as with adhesive) to the inner (lower) annular end of the mediaring. The end cap 122 includes a central circular opening 124dimensioned to receive the support core 56 and enable the filter elementto be removeably located over the support core. A short annular flange126 projects axially downward and bounds opening 124 in end cap 122, toprovide a fluid-tight seal against the sleeve 58 of the support core.Alternatively (or in addition), an O-ring or resilient gasket (notshown) can be provided between the end cap 122 and the support core 56.

The outer end cap 114 also includes a central opening 128, with adiameter somewhat smaller than the opening 124 end cap 122. As shown inFIG. 7, an annular flange 130 bounds the opening 128 in end cap 114, andprojects a short distance axially inward into the filter element fromend cap 114 toward end cap 122 (but terminating at a point much closerto end cap 114 than end cap 122). The protrusions 116 are spacedradially inward from the ring of filtration media 120 and radiallyoutward from flange 130. Flange 130 includes a tapered distal end 132which is dimensioned to engage flush against the dome-shaped end wall 96of the bypass member 76 when the element is located in the housing (see,e.g., FIG. 2). The inner and outer end caps 114, 122 are preferably eachformed of an appropriate material (such as plastic) unitarily (in onepiece) in a conventional manner, such as by molding.

The dome-shaped end wall 96 and bypass spring 102 of the bypass member,and the flange 130 on the end cap 114 provide a bypass valve for thefilter element. When the element is located in the housing, the flange130 engages and seals against the dome-shaped end wall 96, therebypreventing fluid from bypassing the element. When an overpressuresituation exists in the peripheral region 40 of the element, such aswhen the element becomes plugged, the pressure forces bypass member 76inwardly against bypass spring 102, thereby creating a flow gap betweenthe end wall 96 and the flange 130, and allowing fluid to bypass theelement. The spring constant of bypass spring 102 can be chosen todetermine the appropriate cracking force for the bypass feature. Furtherdiscussion of the bypass valve can be found, for example, in U.S. Pat.No. 5,770,054, which is incorporated herein by reference. It is notedthat the bypass valve is an optional feature, and that the filter couldalso be configured without such a bypass valve, in which case end wall96 and spring 102 would be absent, and the end cap 114 would becontinuous (imperforate) across its diameter.

While it is illustrated above that the locking member and bypass memberare received internally of the support core, it is anticipated that withappropriate modifications, the bypass member and locking member couldlikewise be received around (outwardly from) the support core. In thiscase, the bypass member and locking member could function in the samemanner as described above to lock the extension and locking assembly inan outward position when an element is absent from the housing, andallow the extension and locking assembly to move inwardly when anappropriate filter element is located in the housing.

When the element is installed properly in the housing, the fuel enteringinlet port 38 flows into the peripheral region 40 surrounding theelement, and then radially inward through the element to the supportcore 56. The filtered fuel then passes through the support core to theoutlet 39. If an element becomes clogged and a bypass valve is provided,the valve will allow fluid to bypass the element when the fluid pressurein the peripheral region 40 exceeds a predetermined amount. When it isdesirable to change a spent element, the cover 34 is removed (screwedoff), and the element can be easily accessed and replaced with a freshelement. To facilitate the easy grasping of the spent element, theextension and locking assembly 70 automatically pushes the spent elementoutwardly a short distance by virtue of main spring 100. This alsoallows at least some of the fuel to drip off the element and remain inthe filter housing, rather than drip onto the surrounding area duringelement removal.

A second embodiment of the extension and locking assembly 70 isillustrated in FIGS. 10 and 11. In this embodiment, the bypass featureis provided by a separate valve component, indicated generally at 144.Valve component 144 operates in the same manner as the bypass valvedescribed above, and includes a body 146; an enlarged valve head 148;and a pair of elongated and axially-extending fingers 150, each of whichhave a catch 152 at their distal ends. The body 146 of the valvecomponent is received in a circular opening defined by an annularsupport 154 in the locking member, with the catches 152 engaging thesupport 154 to prevent the valve component from being removed fromlocking member 74. Bypass spring 102 extends between the head 148 of thevalve component and an inner annular shoulder 155 of the bypass member,and urges valve component 144 outwardly from the support core.

The enlarged annular head is absent from the locking member 74illustrated in FIG. 11. Instead, the valve head 148 and the catches 152on the fingers 150 of the valve component 144 retain the bypass memberand valve component together. Main spring 100 is applied directly to theenlarged head 94 of the bypass member. The outer end of fingers 157 oflocking member 74 are accessible through the openings 110 in the head 94of the bypass member, and can be engaged by the protrusions 116 on endcap 114 to move the locking member inwardly into the support core. Thelocking member 74 and bypass member 76 otherwise have the sameconfiguration as discussed previously and operate in the same manner tolock the extension and locking assembly in an outward position if anelement is absent, or if an element does not have an appropriatearrangement of protrusion(s).

A further embodiment of the filter element of the present invention isillustrated in FIG. 12. In this embodiment, the protrusions 116 areformed in a separate end piece 160. End piece 160 has an annularconfiguration, and fits against the inside surface of the end cap 114.The end piece 160 can be permanently fixed to the end cap, such as withadhesive, or can merely be located against the end cap and held in placeby friction fit, or by the interaction with the locking member 76. Theangled or helical distal end surfaces of the protrusions are clearlyvisible in this Figure. The remainder of the filter element ispreferably the same as described previously.

Referring now to FIGS. 13–22, a further feature of the present inventionis that a fluid-tight container is provided for the filter element thatsubstantially reduces, if not eliminates, fouling the surrounding areawith dripping fuel. The container is also handy for shipping, andeliminates the need for a shipping carton or box. Referring first toFIGS. 13–16, the container is indicated generally at 164, and includesan imperforate, cup-shaped body 166, and an imperforate lid or cap 168.The cup-shaped body has a sidewall 169 with a cylindrical dimensionslightly larger than the element, and disk-shaped end wall 170. The bodyand lid form a fluid-tight enclosure with a dimension slightly largerthan the element to entirely enclose the filter element. The body alsohas a dimension sufficient to enable it to be inserted into the housingbody 32, between the housing body 32 and the filter element 36.

Lid 168 has an annular, axially extending lip portion 171, which asshown in FIG. 16, closely receives and cooperates with a bead 172bounding the open end of the housing body to enable the lid to be easilyattached to and removed form the body. Other techniques are of coursepossible for easily attaching the lid to the body, such as correspondingscrew threads, and any technique is possible, as long as it allowsrelatively easy attachment and removal of the lid.

The container 164 further includes a retaining device, indicatedgenerally at 174, integral with either the sidewall 119 or end wall 170.As shown in FIG. 15, the retaining device 174 can include a resilientmember, such as an annular channel or ridge 175 formed in the sidewall32, that engages around the outer periphery of end cap 114. The sidewall169 has some resiliency to allow the container body 166 to be easilylocated over the filter element, and snap around the end cap 114 to holdthe end cap against end wall 170.

An alternative embodiment of the retaining device 174 is shown in FIG.17. In this embodiment, an annular bead 178 is formed near the end wall170, and engages the periphery of the end cap 114 when the container islocated over the filter element. The annular bead 178 is likewise formedin sidewall 169, and the sidewall resiliently deflects to allow thecontainer body 166 to be easily located over the filter element.

The body 166 and lid 16 are preferably formed from inexpensive,lightweight material, such as plastic, polypropylene, polyethylene,polycarbonate, PET, or other similar material. The material ispreferably easily incinerated (burned), or at least recyclable. The body166, including retaining device 174, and lid 168 are each preferablyformed unitary (in one piece) by appropriate techniques, such asinjection molding, vacuum-forming or drawing. While the dimensions ofthe body and lid can vary, it is preferred that the body and lid haverelatively thin walls, and it has been found that a body and lid with awall thickness of between 0.015 and 0.030 inches, provides a durable,inexpensive and incineratable product.

As should be appreciated, when the filter element is to be changed, thefresh element is removed from the container 164. The fresh element ispreferably inverted in the container for shipping, and the end caps onthe element can be dimensioned such that the retaining device does notretain the fresh element in the container, or the element is onlyloosely retained. In any case, the body of the empty container is theninverted and located open-end first, down around the filter element.This is facilitated by the element being supported somewhat outwardlyfrom the housing, as discussed above. The container is pushed downwardlyuntil the retaining device is received and snapped around the end cap.The body of the container can then be removed from the housing, therebysimultaneously removing the element. When the container body is freefrom the housing, the container body is quickly inverted to reduce theamount of fuel or oil dripping onto the surrounding area. This alsovirtually eliminates skin-contact with the element and the fuel or oil.Once inverted, the container body catches any remaining fuel or oil, andthe lid 168 can be easily attached to the body 166 to form a fluid-tightenclosure for the element. Since it is preferred that the element iscomprised of combustible materials, the spent element and container canthen be disposed of in an incinerator.

While the retaining device is illustrated above as being unitary withthe sidewall of the container, the retaining device can alternatively beunitary with the end wall 170, or formed as a separate piece andpermanently fixed to the end wall or sidewall. There are numerousembodiments of the retaining device that would be appropriate for thepresent invention. For example, as shown in FIG. 18, the retainingdevice 174 can be formed at the opposite, open end of the container body166, and comprises a channel, ridge or bead 180 in sidewall 169 thatsnaps around the opposite end cap 122 of the element.

FIG. 19 shows a further embodiment, where the container body can includea retaining device 174 comprising a screw thread 181. The screw threadcooperates with end cap 122 to allow the container body to be screwedonto the end cap. The lid (not shown) can then have cooperating internalthreads to allow the lid to be easily screwed onto (and off of) thecontainer body.

FIGS. 20 and 21 show a still further embodiment, where the retainingdevice 174 comprises an annular flange 182 centrally located on the endwall 170 of the container body 166, and received in the central opening128 of the end cap 114 of the element. The flange 182 includes anannular, radially-outward directed catch 186 at the distal inner endthat deformably engages the annular flange 132 surrounding opening 128in end cap 114 to retain the element to the container.

The length of the container body 166 can of course vary, with the lid168 consequently having a longer or shorter axial length such that thetwo components entirely encapsulate the element. As shown in FIG. 22,the container body 166 is shown as a relatively short component, only aslong as necessary that the retainer device 174 snaps around the end cap114 of the element. The lid 168 would then have a relatively long lengthto fully encapsulate the element. Other alternatives are of coursepossible.

Thus, as described above, the filter of the present invention preventsan improper filter element from being used in the filter and preventsoperation of the filter without a filter element in place. Mess andenvironmental issues are substantially reduced, if not eliminated,during an element change. The filter element is also simple and low-costto manufacture.

The principles, preferred embodiments and modes of operation of thepresent invention have been described in the foregoing specification.The invention which is intended to be protected herein should not,however, be construed as limited to the particular form described as itis to be regarded as illustrative rather than restrictive. Variationsand changes may be made by those skilled in the art without departingfrom the scope and spirit of the invention as set forth in the appendedclaims.

1. A filter element including a ring of filtration media circumscribinga central axis and having first and second ends; an end cap assembly atthe first end of the filter media including i) a first flat annular endcap sealingly bonded to the first end of the filtration media, and ii) aseparate annular end piece located against a surface of the first endcap; and a second flat annular end cap sealingly bonded to the secondend of the filtration media; the second end cap including a centralopening along the central axis of the filter element; said end capassembly at the first end of the filter element including a centralopening along the central axis of the filter element, said centralopening of said end cap assembly having a smaller diameter than saidcentral opening of said second end cap, and being defined by an annularflange integral with an inner surface of said end cap assembly andprojecting axially inward from said end cap assembly toward said secondend cap and terminating at a point closer to said end cap assembly thansaid second end cap, said annular flange spaced radially inward from thering of filtration media; and a series of distinct, axially-projectingprotrusions affixed to said annular end piece of the end cap assemblyand spaced radially outward from said annular flange and radiallybetween said flange and said ring of filtration media, said protrusionsprojecting axially inward from said end cap assembly from said end capassembly toward said second end cap and terminating at a point closer tosaid end cap assembly than said second end cap.
 2. The filter element asin claim 1, wherein said protrusions are unitary with said end piece. 3.The filter element as in claim 1, wherein said protrusions are evenlyspaced in an annular arrangement surrounding said annular flange.
 4. Thefilter element as in claim 1, wherein each of said protrusions has adistal free end, and the distal free end of the protrusions has ahelical ramped surface.
 5. The filter element as in claim 1, wherein thering of filtration media radially outwardly bounds the protrusions. 6.The filter element as in claim 1, wherein said flange is spaced radiallyinward apart from the filtration media, and defines an annular gapbetween the flange and the media.
 7. The filter element as in claim 1,wherein said protrusions are radially spaced inward apart from thefiltration media, and radially spaced outward apart from the flange. 8.The filter element as in claim 1, wherein said second end cap has anannular body portion with a surface that is sealingly bonded insurface-to-surface contact with an annular end surface of the filtrationmedia ring.
 9. The filter element as in claim 1, wherein the protrusionsextend in arcuate segments in an annular configuration along an innersurface of the end piece.
 10. The filter element as in claim 1, whereinthe flange is affixed to the first end cap.
 11. The filter element as inclaim 1, wherein the annular flange has a tapered inner distal end. 12.A filter element removably positionable between a pair of housingportions, with a central support core projecting axially away from oneof the housing portions toward the other of the housing portions, saidfilter element comprising: i) a ring of filtration media circumscribinga central cavity along a central axis and having first and second ends,ii) an annular first end cap and annular end piece at the first end ofthe media ring, and iii) an annular second end cap at the second end ofthe media ring; the first end cap having a surface sealingly bonded to asurface at the first end of the filtration media and the end piecelocated in sealing relation with the first end cap to form an integralend cap assembly, and having a series of elongated protrusions extendingaxially inward from said end piece toward said second end cap, saidprotrusions located radially between a central opening in the end pieceand said ring of filtration media, and being radially outwardly boundedby the ring of filtration media; and iii) the second end cap having asurface sealingly bonded to a surface at the second end of thefiltration media; the second end cap also having a central opening alongthe central axis of the filter element, dimensioned to receive thecentral support core, wherein the end piece and protrusions remain withthe filter element when the filter element is removed from between thepair of housing portions.
 13. The filter element as in claim 12, whereinthe protrusions are permanently affixed to said end piece.
 14. Thefilter element as in claim 12, wherein the protrusions are unitary withthe first end piece.
 15. The filter element as in claim 12, wherein thefirst end cap includes a central flange outwardly bounding a centralopening in the first end cap, and projecting axially inward from thefirst end cap toward the second end cap and terminating at a pointcloser to the first end cap than the second end cap, the flange locatedradially inward from the protrusions.
 16. A filter element removablypositionable within a housing, the filter element including a ring offiltration media circumscribing a central axis and having first andsecond ends; an end cap assembly at the first end of the filter mediahaving a first annular end cap sealingly bonded to the first end of thefiltration media, and a second annular end cap sealingly bonded to thesecond end of the filtration media; the second end cap including acentral opening along the central axis of the filter element; said endcap assembly at the first end of the filter element including a centralopening along the central axis of the filter element, said centralopening of said end cap assembly having a smaller diameter than saidcentral opening of said second end cap, and being defined by an annularflange integral with an inner surface of said end cap assembly andprojecting axially inward from said end cap assembly toward said secondend cap and terminating at a point closer to said end cap assembly thansaid second end cap, said annular flange spaced radially inward from thering of filtration media; and a series of axially-projecting protrusionsaffixed to said end cap assembly and located radially between saidannular flange and said ring of filtration media, said protrusionsprojecting axially inward from said end cap assembly from said end capassembly toward said second end cap and terminating at a point closer tosaid end cap assembly than said second end cap, wherein the end capassembly remains with the filter element when the filter element isremoved from between the housing portions.
 17. The filter element as inclaim 16, wherein said end cap assembly further comprises an annular endpiece located in surface-to-surface relation with a surface of the firstannular end cap, the protrusions being unitary with the annular endpiece.
 18. The filter element as in claim 17, wherein the annular endpiece is located against an inner surface of the first end cap.
 19. Thefilter element as in claim 18, wherein said protrusions are spacedradially outward apart from said annular flange.